This invention relates to a razor blade assembly in the form of a razor, or a shaving unit adapted to be mounted on a razor handle to form a razor.
Such razor blade assemblies conventionally comprise a razor blade, or preferably two superimposed spaced-apart and staggered razor blades, mounted on a blade platform and supported within a frame, the frame including a guardbar which in use contacts the face of the shaver, and a top cap. When in use, the edge of the blade or of each blade should lie between and parallel to the guardbar and the forward edge of the top cap at a correct exposure for shaving, i.e. in a shaving position.
When the razor or shaving unit is to be stored away it is preferable that the blade edge or each blade be withdrawn from the shaving position, so that the razor or shaving unit cannot harm anyone handling it.
It has been proposed, in German Offenlegungsschrift No. 2938975, to provide a razor in which the blade can be caused to slide relative to the guardbar and top cap in a plane between the shaving and withdrawn positions.
It has also been proposed, in U.K. Patent Specification No. 2066131A, to achieve the effect of withdrawing the blade by causing the top cap to slide in a forward direction screening the blade edge.
The difficulty associated with mounting a razor blade for movement within a razor frame is that the positioning of the blade edge or edges relative to the guardbar and top cap is critical and extremely close tolerances must be adhered to if the shaving geometry and hence the shaving quality of the razor is to be maintained through repeated blade movements, which also means that any moving parts must be subject to very little wear.